By Jim Klett, Professor and Cooperative Extension Landscape Horticulturist, Colorado State University Department of Horticulture and Landscape Architecture
If you want the last word about new annual plants and how they will perform in the Rocky Mountain region, you need look no further than the W.D. Holley Plant Environmental Research Center (PERC) at Colorado State University in Fort Collins.
There, in the All-American Selection Display garden, horticulturists, in 1996, grew more than 625 annual varieties of bedding plants.
Twenty seed companies provided seed and financial support for the garden. Faculty and students from the Department of Horticulture and Landscape Architecture managed the project, and growers, seed company personnel and horticulturists offered advice.
When the planting, growing and judging were finished, Celosia cristata 'Prestige Scarlet,' was named outstanding new variety in 1996. Introduced by Sakata Seed Company, this Celosia also is a 1997 All-America Selection. In the trials, 'Prestige Scarlet' produced a uniform flower in a brilliant scarlet color that stayed through most of the growing season. This plant grows to 10 to 12 inches high and about the same in width.
Zinnia 'Dreamland Mix' was named Best of Show, primarily because of its good growth habit and wide variety of flower colors. Introduced by American Takii, this zinnia mix is uniform in height, growing from 15 to 18 inches tall and about 15 inches wide. It would be a good choice for cut flowers.
Among other highly rated plants is Dianthus 'Floral Lace Violet Picotee' from Ball Seed Company. This plant is uniform and compact, reaching from 10 to 12 inches tall and about the same in width. Its lace-like flower petals are a deep rose color. This Dianthus shows well through the entire growing season, without any mid-summer lull in flowering or overall appearance.
Best zonal geranium was 'Designer Hot Pink' from Ball FloraPlant. These geraniums were propagated asexually from cuttings. 'Designer Hot Pink' flowers are hot pink in color and grow, with good uniformity, to 10 to 12 inches high and 12 to 14 inches wide.
Best seed geranium was 'Pinto Scarlet' from S & G Sandoz, a plant with the strong selling point of appearing to hold up well after rains. 'Pinto Scarlet' grows 16 to 18 inches high and 12 to 15 inches wide. It blooms scarlet and red, with abundant, large-sized flowers.
'Acapulco,' from Fischer Geraniums, was best cascade or ivy geranium. These geraniums, which feature a spreading growth habit, bloom purplish/pink flowers that cover the entire plant. They grow to about 12 inches high with a 15-to-18-inch spread. 'Acapulco' would make an excellent ground cover or hanging basket plant.
Two varieties tied for best Impatiens -- 'Dazzler Rose' and 'Showstopper Tropical Punch,' both from Ball Seed Company. Both varieties grow uniformly to 15 to 18 inches high and about the same width. 'Dazzler Rose' is more of a rose flower color, while 'Showstopper Tropical Punch' is a salmon-orange color.
Best Marigold was 'Safari Tangerine' from Bodger Seed Company. These plants average 15 to 18 inches in height and about 12 inches wide. With orange/yellow blooms, this variety of marigold appears vigorous in growth habit and bore flowers throughout most of the growing season. Late in the season, some aster yellows occur on the plant, a feature that was prevalent on almost all marigold varieties in the trials.
Two varieties, 'Dreams Midnight' and 'Fantasy Blue,' tied for best petunia in the trials. 'Dreams Midnight,' which is a grandiflora petunia with a violet-blue flower, is from Pan American Seed Company. It is a uniform plant with many flowers. 'Fantasy Blue,' which was developed from Goldsmith Seeds, features many smaller blue flowers. This mini-style petunia grows to about eight inches in height and 12 to 15 inches wide.
All of these varieties will be available this Spring in area garden centers and nurseries.PERC
Colorado State's W.D. Holly Plant Environmental Research Center (PERC) at 630 W. Lake St., in the southwest corner of the campus, has been home to the annual trial gardens since they began in 1979. In 1998, the university was chosen as one of two All-American Selection outdoor test gardens in Colorado.
For the 2001 growing season approximately 550 different varieties, including all the geraniums, petunias, and verbenas and the All-American Selections, were planted at a new and more visible site at High School Park on College Avenue and Remington Street in Fort Collins.The gardening public is welcome to visit the trials this season at High School Park on College Avenue and Remington Street in Fort Collins. For a complete research repot of the annual trial gardens, contact the Department of Horticulture and Landscape Architecture, Colorado State University, Fort Collins, CO 80523. There is a charge to cover the cost of printing, handling and shipping.
Photograph courtesy of All-American Selections.
© CSU/Denver County Extension Master Gardener 2010
888 E. Iliff Avenue, Denver, CO 80210
Date last revised: 01/05/2010